Rotary engine.



PATENTED JAN. 30, 1906.

A. E. STEVENS. ROTARY ENGINE. APPLICATION FILED M1514, 1905.

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ALONZO E. STEVENS, OF DALLAS CENTER, IOWA.

ROTARY ENGINE.

Specification of Letters Patent.

Patented Jan. 30, 1906.

Application ld May 4:, 1905. Serial N0. 258,867-

l gine that is very simple and not difficult and costly in construction; second, to increase the maximum of power of any given size of cylinder; third, to apply a continuous live-steam pressure during each revolution of the driving-shaft and also at the same time utilize a continuous expansive force during each revolution of the driving-shaft.

My invention consists in the construction, arrangement, and combination of elements and subcombinations, as hereinafter set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which- Figure 1 is a vertical sectional view that shows the peculiar shape of a cylinder that is circular at one end portion and rectangular at its other end, a shaft in concentric position with the circular end, a segmental piston of peculiar shape on the shaft, a vibratory abutment or valve in the rectangular end, and a steam-chamber and rotary valve on the top of the rectangular chambers. Fig. 2 is a face view of one side of the cylinder closed by a circular head. and shows an eccentric on the end of the shaft connected with the crank of a rotary valve in the steam-chamber on top of the rectangular end of the cylinder. Fig. 3 is a top view of one of the vibratory abutment-valves, and Fig. 4 a transverse sectional view of the same. Fig. 5 is a longitudinal sectional view of the valve-chamber and rotary valve therein. Fig. 6 is a longitudinal sectional view that shows the cylinder divided into two uniform chambers by a midway partition and pistons of uniform shape and size and abutment-valves of uniform shape and size in the chambers, but the pistons and the valves in different positions relative to each other and to the two chambers.

The numeral 10 designates the circular portion of the cylinder, and 12 the rectangular end thereof, that is closed at its end by a flat plate 13, fixed thereto by means of tapscrews or in any suitable way. The cylinder is divided into two chambers of uniform shape and size by an integral partition 14, and t e outer sides of the circular portions of the two chambers are closed by circular heads 15, fixed to the cylinders by means of tap-screws, as shown, or in any suitable way.

A driving-shaft 16 is in concentric bearings in the heads 15 and the partition 14`and so id segmental pistons 17 and 18 of uniform semicircular shape and size are fixed to the shaft in different positions relative to the shaft, as shown in Fig. 6. The outer edges of the pistons are concentric with the circular end portions of the two steam-chambers and,

have shoulders 19 at one end and outwardlycurved shoulders 2O at their other ends, as shown in Fig. 1.

' Abutment-valves 21 and 22 are fixed to short rock-shafts 23 by means of screws or in any suitable way, and journaled in the integral sides of the rectangular ends of the chambers and the partition 14. The free ends of these valves are in constant contact with the peripheries of the pistons 17 and 1S as the pistons revolve and as required to produce` chambers for live steam and also for steam expansion at each revolution of each piston.

The abutment-valves 21 and 22 are composed each of two parts tongued and grooved at their inner edges and provided with suitable packing 24 at their outer edges and free ends, as shown in Fig. 3. A leaf-spring 25, fitted between their inner edges, normally presses outward, as required, to compensate for wear on their outer edges as' required to maintain steam-tight chambers.

An elongated valve-chamber 26 is fixed on top of the rectangular ends of the steamchambers and provided with a central opening in its top for connecting a pipe 27 therewith to convey steam into the valve through a coinciding opening 28 in the valve 29, fitted in the valve-chamber. In the end portions of the valve are elongated ports 3() and 31 for admitting steam into the rectangular ends of the two steam-chambers at each revolution IOO of the pistons, but at different intervals of Therefore the ports are not in alinewith the valve-crank 32, as shown in Fig. 2,

in such a manner that the crank and valve in the valve-chamber will be vibrated at each revolution of the shaft 16 as required to alternately bring the ports 30 31 into coincid- IIO ing positions with induction-ports 35 and 36 in the tops of the rectangular ends of the steam-chambers.

Each steam-chamber is provided with an exhaust-port 37 at its bottom, as shown in Fig. 1.

By the peculiar form of the solid segmental piston and the abutment-valve in the segmental chamber the valve engages the periphery of the hub of the piston and also its outwardly-curved end, as Well as the outer surface, and'thus continuously separates the circular chambers of the cylinder from the rectangular chamber, and before the square end of the piston closes the exhaust-port the steam will have exhausted from between the curved end of the piston and the abutting valve, so there will be a vacuum between the lower side of the valve and the outwardlycurved end of the piston.

In the practical operation of the engine thus constructed when one of the ports 3() or 31 is in coinciding position with one of the ports in the top of the wall of one of the rectangular ends of one of the steam-chambers said end of the chamber will be filled with live steam, that will press against the square shoulder 19 of the piston 17 to rotate the piston, and when the piston has made about a quarter-revolution the rotary valve 29, connected with the shaft 16, will vibrate and close communication with the chamber that has the live steam, and confined steam will then expand and by its expansive force press the piston forward another quarter-revolution and allow it to escape through the exhaust-port 37, and when the pressure is thus relaxed on the one piston after it has made over a half-revolution the position of the rotary valve 29 is reversed and live steam is let into the second rectangular steam-chamber to press against the square shoulder 19 of the second piston 18 to actuate the piston in the same manner that the piston 17 was actuv ated. By the joint action of the two pistons a continuous live-steam pressure and also a continuous expansive-steam pressure is produced as required to produce a complete revolution of the shaft 16 and a continuous rotary motion of the engine.

It is obvious when steam is exhausted through the ports 37 at the bottom of the engine the peripheries of the hubs 3S of the pistons will contact with the free ends of the abutment-valves 21 and 22 and lift them as required to allow the outwardly curved shoulders 20 of the pistons to pass upward from under the valves and at the same time prevent steam from passing downward from the rectangular steam-chambers into which the live steam enters at each revolution of the pistons. It is also obvious that pairs of steam-chambers and pistons may be connected with one driving-shaft as required to produce a compound rotary engine.

Having thus set forth the purpose of my invention and the construction and function of each element and the arrangement and combination of all the parts, the practical operation and utility of the invention of the engine will be apparent to persons familiar with the art to which it pertains.

What I claim as new, and desire to secure by Letters Patent, isv 1. In a rotary steam-engine, a solid semicircular piston, having one square end and one outwardly curved, on a shaft in concentric position with a circular chamber having a second chamber communicating therewith and an abutment-valve in the second cham-` ber to continuously engage the piston at each revolution as set forth.

2. In a rotary engine, a circular cylinder having a rectangular chamber communicating therewith, a driving-shaft in the center of the circular cylinder anda solid semicircular piston on the shaft to rotate Within the circular chamber of the cylinder and one end of the piston square and the other end curved outwardly and an abutment-valve pivoted in the rectangular chamber to contact with the piston as the piston revolves in the circular chamber. Y

3. In a rotary engine, a circular cylinder having a rectangular chamber communicating therewith, a driving-shaft in the center of the circular cylinder and a semicircular piston, square at one end and curved outwardly at the other end, on the shaft to rotate within the circular chamber of the cylinder, an abutment-valve pivoted in the rectangular chamber to contact with the piston as the piston revolves in the circular chamber and a rotary valve connected with the rectangular chamber to admit steam into the rectangular chamber at each revolution of the shaft and piston.

4. In a rotary engine, a circular cylinder having a rectangular chamber communicating therewith, a driving-shaft in the center of the circular cylinder and a semicircular piston, having a square shoulder at one end outwardly curved at the other end, on the shaft to rotate within the circular chamber of the cylinder, an abutment-valve pivoted in the rectangular chamber to contact with the piston and the hub of the piston as the piston revolves in the circular chamber, a rotary valve connected with the rectangular chamber to admit steam into the rectangular chamber at each revolution of the shaft and piston and means to actuate the rotary valve during an interval in each revolution of the shaft.

5. In a rotary engine, a circular cylinder having a rectangular chamber communicating therewith, a driving-shaft in the center of the circular cylinder and a semicircular piston, square at one end outwardly curved at its other end, on the shaft to rotate within IOO IIO

the circular chamber o'l' the cylinder, an abutment-valve pivoted in the rectangular chaml ber to contact with the piston and the hub of the piston as the piston revolves in the circular chamber, a rotary valve connected With the rectangular chamber to admit steam into the rectangular chamber at each revolution ofthe shaft and piston, a crank on the end of the rotary valve, an eccentric on the end of the driving-shaft and an arm pivotally connected with said crank and said eccentric to actuate the rotary valve during an interval in each revolution of the shaft.

6. A circular cylinder having a rectangular extension, a central partition to produce tWo circular steam-chambers and two rectangular steam-chambers, a driving-shaft in concentric position With the tWo circular chambersI a semicircular piston in each circular chamber ixed to the shaft and one end of each piston square and the other end curved outwardly, an abutment valve pivoted in each rectangular chamber to engage a piston and means to alternately admit steam into the rectangular chamber.

7. In a rotary engine, a circular cylinder having an angular extension7 a driving-shaft in the center of the circular portion ol the cylinder, a piston having a square shoulder and also an outwardly-curved shoulder fixed to the shaft and an abutment-valve pivoted in the angular part of the cylinder to engage the piston as set forth.

ALONZO E. STEVENS.

Witnesses C. L. Koor-I,V D. K. MILLER. 

